well there is a different approch but same as it need some code to printf()

Mastering STM32 book

with adding retarget files (.c and .h source and header files) your code.

for preventing function conflict you should convert this code to comments in syscalls.c

/*
int _close(int file)
{
  (void)file;
  return -1;
}

int _fstat(int file, struct stat *st)
{
  (void)file;
  st->st_mode = S_IFCHR;
  return 0;
}

int _isatty(int file)
{
  (void)file;
  return 1;
}
*/

no further setting needs,